California is bracing for worst-ever wildfire season, Gov. Brown says

California is bracing for its worst-ever wildfire season which could cripple the state's economy, Gov. Jerry Brown said Sunday.

Brown told ABC's "This Week" that the nearly dozen wildfires, which caused more than $20 million in damage, mark only the beginning. Brown says the state has 5,000 firefighters on the job and has set aside $600 million to battle the blazes, but worries that might not be enough.

"We're getting ready for the worst," Brown said. "Now, we don't want to anticipate before we know, but we need a full complement of firefighting capacity."

So far, the California Department of Forestry and Fire Protection has responded to more than 1,500 fires this year, compared with about 800 during an average year.

Brown said his state is on the "front lines" of climate change, which is making California weather even hotter.

"And in the years to come, we're going to have to make very expensive investments and adjust. And the people are going to have to be careful of how they live, how they build their homes and what kind of vegetation is allowed to grow around them.

Unusually high temperatures, low humidity and gusty winds set conditions last week for the string of wildfires that broke out in San Diego County.

"Normally, I don't even put wildfire gear in my vehicle until the end of April. This year I never took it out," Kirk Kushen, battalion chief of the Kern County Fire Department, said at a base camp in Escondido. "We never really completed the 2013 fire season. It's been a continuation."

At least 10 fires spanning 39 square miles chewed a destructive path through San Diego County, destroying 11 houses, an 18-unit apartment complex and two businesses. A badly burned body was found in a transient camp, and one firefighter suffered heat exhaustion.

The last of tens of thousands of evacuees returned home Saturday after firefighters scoured charred hillsides north of San Diego to guard against a resurgence of flames that ripped through the region.

The first blaze in San Diego started Tuesday and was caused by a spark from construction equipment, according to state officials, but it could take months to get to the bottom of the most damaging fires. Alberto Serrato, 57, pleaded not guilty Friday to an arson charge in connection with one of the smaller fires, but authorities say they don't believe he started it, just added brush to it.

In the California city of Modesto, a fire fueled by hot weather and high winds on Friday quickly spread to a row of townhouses, destroying three of the structures and damaging six others. Authorities said the blaze started on the grassy berm of a freeway project frequented by homeless people.

Ocean breezes and lower temperatures over the weekend allowed firefighters to get the upper hand on a 4-square-mile blaze that started in the suburb of San Marcos and three fires at Camp Pendleton.

Firefighters doused remaining hotspots with hoses and water-filled backpacks, sawed large logs and raked soil with shovels and other hand tools to ensure the ground was moist enough to prevent fires from returning.

Kushen, who was working his 10th straight day and was nearly 27 hours into his shift as his team prepared to go rest at a hotel, saw between 15 and 20 destroyed houses or other structures while combing the hills in and around San Marcos for smoke and smoldering brush.

San Marcos, a suburb of 85,000 people where strip malls and new housing tracts mix with older homes, slowly returned to normal as more roadblocks were removed.

"It's such a wonderful blessing to be back," Jamie Williams said as he unloaded three bags of clothing from his car that he took when ordered to evacuate Wednesday night. "It was almost a teary-eyed kind of thing."

The state firefighting agency went to peak staffing in the first week of April, instead of its usual start in mid-May.

Battalion Chief Kevin Taylor of the Paso Robles Fire Department in central California usually doesn't leave home until late July to assist other agencies during the fire season. He was dispatched to the Los Angeles area in January and led a crew that began work near San Diego on Thursday.

"There hasn't been a break," said Taylor, as he ate lunch under a shaded tree amid orders to be ready to move on three minutes' notice. "It's almost a 12-month fire season."